Association of a common dog leucocyte antigen class II haplotype with canine primary immune-mediated haemolytic anaemia

Immune-mediated haemolytic anaemia (IMHA) is the commonest immune-mediated disease of the dog, representing a major health concern to this species. The aim of this investigation was to determine whether genetic susceptibility to IMHA is associated with genes of the canine major histocompatibility complex (MHC; dog leucocyte antigen system, DLA). Samples were collected from 108 dogs with primary idiopathic, Coombs' positive IMHA. This diseased population was subdivided on the basis of Coombs' test results into two groups: 1) dogs with dominant warm-reactive immunoglobulin (Ig) G haemagglutinins and (2) dogs with an additional or dominant cold-reactive IgM haemagglutinin. The DLA class II alleles and haplotypes of the diseased population were characterised, and these data were compared with those derived from a breed-matched control cohort and a much larger group of DLA-typed dogs. Two haplotypes were increased in the patient group: DLA-DRB1*00601/DQA1*005011/DQB1*00701 (in the group with warm-reactive IgG haemagglutinins only) and DLA-DRB1*015/DQA1*00601/DQB1*00301 (in both groups, but more so in the group with cold-reactive IgM haemagglutinins). One haplotype, DLA-DRB1*001/DQA1*00101/DQB1*00201, was decreased in the total patient group, but this decrease was limited to the warm-reactive IgG haemagglutinins group, and it was actually increased in the cold-reactive IgM haemagglutinins group. A second haplotype, DLA-DRB1*015/DQA1*00601/DQB1*02301, was also decreased in the total patient group, and this decrease was found in both subgroups. In addition, all haplotypes carrying DLA-DRB1*001 were significantly increased in the cold-reactive IgM haemagglutinins group. When the overall patient group was divided on the basis of individual breeds with more than six animals represented, each of the haplotypes could be shown to be implicated in one of the breeds. Thus, it was apparent that different breeds had different MHC associations with canine IMHA, which is similar to the observation that different human ethnic groups can have different HLA associations with the same immune-mediated disease.     

Frequency and distribution of alleles of canine MHC-II DLA-DQB1, DLA-DQA1 and DLA-DRB1 in 25 representative American Kennel Club breeds

The frequency and distribution of dog leucocyte antigens (DLA) class II -DQA1, -DQB1 and -DRB1 alleles were determined for 25 American Kennel Club (AKC) registered dog breeds, representing 360 dogs from each of the seven major performance categories. Six to twenty-eight (average n=11) dogs were studied per group, with the exception of the Akita dog (n=94). All dogs were unrelated with no common grandparents based on AKC pedigree records (F-value <0.125). DLA class II allelic diversity was broad across breeds; 31/61 published DLA-DRB1 alleles, 11/18 published DLA-DQA1 alleles and 31/47 published DLA-DQB1 alleles were found among the 25 breeds. However, allelic diversity was severely limited within a breed. Seventeen of the DLA-DRB1 alleles were each found in only a single breed, and only seven alleles were shared by seven or more breeds. DLA-DRB1*00101 and DLA-DRB1*01501 were shared by 16 and 19 breeds, respectively. DLA-DQA1*00101 and DLA-DQA1*00601 alleles were shared by many breeds. The Rough Collie (DLA-DQA1*00901), English Setter (DLA-DQA1*00101) and Scottish Terrier (DLA-DQA1*00101) were monoallelic for DLA-DQA1. Eleven DLA-DQB1 alleles were each found only in a single breed and only seven alleles were shared by six or more breeds. DLA-DQB1*00201 and DLA-DQB1*02301 were shared by 17 and 18 breeds, respectively. Forty per cent of dogs typed were homozygous at DLA-DRB1, 52% at DLA-DQA1 and 44% at DLA-DQB1. Nine new DLA class II alleles were identified; three for DRB1 and six for DQB1. Comparison of our study of North American purebred dogs to previous European DLA surveys showed a similar use of common alleles consistent with known founder effects. However, more alleles were detected in European breeds, compared to their North American descendents, indicating that additional DLA class II diversity was lost when European breeds were established in North America.     

A description of cutaneous-subcutaneous pythiosis in fifteen dogs.

Information regarding signalment, duration of clinical signs, history of swimming, results of CBC and serum biochemical analyses, biopsy findings and mycological results, together with treatments and outcome, was retrieved from the medical records of 15 dogs with a diagnosis of pythiosis made between 1985 and 1995 at the Colleges of Veterinary Medicine, North Carolina State University and the University of Florida. Most of the dogs were young (median age 22 months) and represented larger breeds (> 20 kg). Lesions were characteristically chronic, ulcerated, and nodular with multiple draining tracts on the limbs, thoracic wall or perineal regions. The median duration of these lesions was 3 months with a range of 2 weeks-6 months. Seven dogs had a history of swimming. Peripheral eosinophilia was observed in 14 of the dogs. Cytological evaluation of discharge, aspirates, or impression smears made from biopsy specimens revealed hyphae in five of 11 dogs (45%). Histopathological evaluation using the Gomori Methenamine-Silver (GMS) stain was the most useful test for providing presumptive evidence of cutaneous pythiosis. Immunotherapy or antifungal therapy using either amphotericin B, liposomal nystatin, itraconazole, or ketoconazole were all unsuccessful. The only dog to survive underwent amputation of the affected limb; thus, the prognosis for cutaneous pythiosis in the dog is poor.     

Haematology and clinical chemistry of english springer spaniel dogs with phosphofructokinase deficiency

Haematologic and serum clinical chemical values were compared from five to nine phosphofructokinase (PFK)-deficient (when not in haemolytic crisis) and five normal adult English springer spaniel dogs. Affected dogs had macrocytic hypochromic compensated haemolytic anaemias (haematocrit 0.35 ± 0.021/l, mean ± standard deviation), with markedly increased absolute reticulocyte counts of 859 ± 320 × 10⁹/l (normal control dogs, 29 ± 10 × 10⁹/l). Bone marrow evaluation of affected dogs revealed erythroid hyperplasia with normal or increased amounts of stainable iron, as would be expected in response to a haemolytic anaemia. Although the platelet count was not different from that of normal control dogs, the mean platelet volume was nearly 50% higher in affected dogs. Absolute numbers of neutrophils, lymphocytes, and monocytes were higher in affected dogs (10.7 ± 1.3, 4.4 ± 1.2 and 1.4 ± 0.5 × 10⁹/l, respectively) than in normal control dogs (6.8 ± 1.4, 3.0 ± 0.3 and 0.5 ± 0.2 × 10⁹/l, respectively). Affected dogs also had higher serum iron (58 ± 25 mol/l) and ferritin (1081 ± 172 g/l) concentrations than normal control dogs (24 ± 5 mol/l and 512 ± 222 g/l, respectively), providing evidence for increased body iron stores. Serum haptoglobin was very low in most affected dogs, indicating that some degree of intravascular haemolysis occurs even when haemoglobinuria is not observed. Serum chemical analysis revealed slightly higher potassium, magnesium, and calcium values in affected dogs compared to normal dogs. Consistent with the presence of a haemolytic anaemia, serum bilirubin from affected dogs was increased in most affected dogs (14 ± 8 mol/l compared to 2 ± 1 mol/l in normal control dogs). Serum urea was also higher (10.9 ± 2.8 v 6.2 ± 1.3 mmol/l), but creatinine was lower (53 ± 8 v 85 ± 12 mol/l) in affected dogs, compared to normal control dogs. Serum creatine kinase, lactate dehydrogenase, and alkaline phosphatase from affected dogs were at least double that of normal control dogs. Serum protein and total globulins were slightly higher, but albumin was slightly lower in affected compared to normal control dogs.     

The assay of canine serum haptoglobin and its diagnostic implications. A comparison of two assay techniques

A Sephadex gel filtration technique was compared with a radial immunodiffusion (RID) method for the assay of serum haptoglobin in the dog. Administration for a haemolytic agent (acetylphenylhydrazine) to dogs resulted in reduced serum haptoglobin but without a significant change in red cell indices. It is suggested that the assay of serum haptoglobin in the dog may be of value in detecting low grade haemolysis when other criteria fail. After standardising the assay using the gel filtration technique, a number of samples can be screened simultaneously using RID thus enabling routine clinical laboratory monitoring for haemolysis. The clinical value of serum haptoglobin assay in the diagnosis of canine haemolytic anaemia is discussed.     

Dog leucocyte antigen class II diversity and relationships among indigenous dogs of the island nations of Indonesia (Bali), Australia and New Guinea

The genetic polymorphism at the dog leucocyte antigen (DLA) class II loci DQA1, DQB1 and DRB1 was studied in a large genetically diverse population of feral and wild-type dogs from the large island nations of Indonesia (Bali), Australia and New Guinea (Bali street dog, dingo and New Guinea singing dog, respectively). Sequence-based typing (SBT) of the hypervariable region of DLA-DRB1, -DQA1 and -DQB1 alleles was used to determine genetic diversity. No new DQA1 alleles were recognized among the three dog populations, but five novel DLA-DRB1 and 2 novel DLA-DQB1 allele sequences were detected. Additional unknown alleles were postulated to exist in Bali street dogs, as indicated by the large percentage of individuals (15%-33%) that had indeterminate DRB1, DQA1 and DQB1 alleles by SBT. All three groups of dogs possessed alleles that were relatively uncommon in conventional purebreds. The New Guinea singing dog and dingo shared alleles that were not present in the Bali street dogs. These findings suggested that the dingo was more closely related to indigenous dogs from New Guinea. Feral dog populations, in particular large ones such as that of Bali, show genetic diversity that existed prior to phenotypic selection for breeds originating from their respective regions. This diversity needs to be identified and maintained in the face of progressive Westernization. These populations deserve further study as potential model populations for the evolution of major histocompatibility complex alleles, for the study of canine genetic diversity, for the development of dog breeds and for studies on the comigration of ancestral human and dog populations.     

Seroprevalence of Toxoplasma gondii and Neospora caninum in dogs from Korea

Toxoplasma gondii and Neospora caninum are closely related protozoan parasites, they share many common hosts, and can cause neurological diseases in dogs. Dogs can have close contacts with humans and livestock and therefore they can act as reservoirs of these parasites. The aim of this study was to survey the seroprevalence of antibodies against T. gondii and N. caninum and their co-infection rate in dogs in Korea. In total, sera from 553 domestic dogs were collected from different breeds, sexes, and ages of dogs from nine provinces across the country of Korea during 2006 and 2007. The presence of antibodies against T. gondii and N. caninum was analyzed using the latex agglutination test (LAT) with a cut-off value of 1:32, and the indirect fluorescent antibody test (IFAT) using a serum titer of 1:100. In the total dog population, 71 (12.8%) dogs were positive for anti-T. gondii antibodies and only 20 (3.6%) were positive for anti-N. caninum antibodies. Relatively higher seropositive frequencies of antibodies against T. gondii (20.1%) and N. caninum (4.9%) were detected in the dog population from the Gyeonggi. A higher proportion of animals seropositive for anti-T. gondii antibodies was found in stray dog populations as compared to household dog populations: 18.5% (59/319) vs 5.1% (12/234), respectively. The Chi-square tests revealed significant differences in the seropositive frequencies of antibodies against T. gondii between stray and household dogs in the total population (p<0.0001), and in dogs from the Gyeonggi (p<0.01). No significant differences were observed for the presence of antibodies against T. gondii or N. caninum when compared across the sex or age (p>0.05). The first serological survey on antibodies against both T. gondii and N. caninum parasites across the entire country showed that co-infection was not common in these canine populations with a seropositive level of 0.72%. The significantly higher positive frequency of T. gondii antibodies in stray dogs in both, Gyeonggi and in the total dog populations suggests that further investigation on the seroprevalence of parasites should focus on stray dogs.     

Evaluation of Immunity and Seropositivity of IgG Antibodies to Canine Parvoviruses in Vaccinated and Unvaccinated Dogs in Abeokuta,Nigeria

Canine Parvovirus (CPV) is a very contagious and virulent viral disease affecting domestic dogs all over the world causing high morbidity and mortality in dogs, especially puppies. This study aimed at determining the seropositivity of IgG antibodies against CPV in vaccinated and unvaccinated dogs and to evaluate the immune status of dogs presented in Abeokuta. Forty-eight dogs were enrolled in this study. These dogs were presented at random for treatment, routine checkup, and vaccination at the State Veterinary Hospital and Veterinary Teaching Hospital all in Abeokuta. All the dogs were fully maintained under domestic setting. Selection for study was done based on thorough examination of the dogs and their medical records. The clients were informed of the nature of the investigation. Blood samples were collected and analyzed for anti-CPV-IgG. In principle, protective immunity correlates with high antibody titers and this was determined using a commercially available immunocomb® test kit for anti-CPV IgG antibody. Of 48 dogs sampled, 38 (79.2%) had high level of anti-CPV antibody titer and 10 (20.8%) had low level of anti-CPV antibody titer. Twenty six (54.2%) were males while 22 (45.8%) were females. Forty-five (93.75%) dogs were exotic breeds while 3 (6.25%) dogs were mongrels. Thirty (62.5%) of the dogs were less than one year old and the age range of all dogs sampled was between 7 weeks and 7 years. There was no significant difference (P > 0.05) between sex and the level of immunity but significant differences (P < 0.05) were observed between ages of dogs, breeds, post-vaccination period, and the level of immunity. In conclusion, this study has further confirmed the presence of IgG antibodies against canine parvovirus among dogs in Abeokuta, Nigeria. Of all variables evaluated, ages of dogs, breeds and post-vaccination period were the main correlates of the level of immunity to CPV. This study also showed agreement with previous studies in the diagnostic value of using the immunoblot ELISA assay for the rapid detection of anti-CPV IgG antibody.     

Bone marrow pathology in dogs and cats with non-regenerative immune-mediated haemolytic anaemia and pure red cell aplasia

Many dogs and cats with immune-mediated haemolytic anaemia (IMHA) lack a bone marrow erythroid regenerative response. To better understand the failure of the bone marrow to respond to the anaemia, bone marrow pathology associated with non-regenerative IMHA and pure red cell aplasia (PRCA) was reviewed. Eighty-two affected dogs and 57 affected cats were identified from a population presenting to a referral hospital over a 10-year period. Fifty-five dogs had non-regenerative IMHA (38 had bone marrow erythroid hyperplasia and 17 had erythroid maturation arrest) and 27 had pure red cell aplasia (PRCA). Twenty-eight cats had non-regenerative IMHA (24 had erythroid hyperplasia and 4 had erythroid maturation arrest) and 29 had PRCA. A variety of pathological changes were observed in bone marrow aspirates and core biopsy specimens taken from these animals. These changes included dysmyelopoiesis, myelonecrosis, myelofibrosis, interstitial oedema, haemorrhage, acute inflammation, haemophagocytic syndrome, lymphocyte aggregation, and lymphocyte or plasma cell hyperplasia. In both dogs and cats, dysmyelopoiesis, myelonecrosis, myelofibrosis, interstitial oedema, haemorrhage, acute inflammation and haemophagocytic syndrome were primarily noted in bone marrow specimens where there was evidence of erythroid hyperplasia. These animals were also more often neutropenic and thrombocytopenic, and had decreased 60 day survival when compared with dogs or cats with non-regenerative anaemia associated with erythroid maturation arrest or PRCA. Therefore, the pathogenesis of the non-regenerative anaemia in non-regenerative IMHA may involve both antibody-mediated destruction of bone marrow precursor cells and pathological events within the bone marrow that result in ineffective erythropoiesis.     

Haematological parameters and altered erythrocyte metabolism in anaemic dogs

In previous studies, an increase in the activity of pyruvate kinase (PK) and glucose-6-phosphate dehydrogenase (G6PDH), an increase in the concentration of 2,3-diphosphoglycerate (2,3DPG), and alterations in osmotic fragility were found in dogs with haemolytic anaemia. These changes were mainly caused by the presence of immature red cells found in regenerative anaemias. In the present study, the same parameters were evaluated in dogs with different types of anaemia. The haematological patterns of 40 anaemic dogs were analysed to define the pathogenesis and the haematological features of each case. Non-regenerative anaemias could be attributed principally to chronic diseases and to the haemolysis that accompanies the early stages of canine babesiosis. Regenerative anaemias were mainly due to haemolysis, in some cases with an immune-mediated pathogenesis. PK activity was higher in regenerative than in non-regenerative anaemias, but G6PDH activity and 2,3DPG concentration increased in both types of anaemia. This suggests that PK activity is influenced by the presence of immature red cells, but the requirements for reducing compounds and oxygen are not dependent on the type of anaemia. Abnormalities in osmotic fragility were detected in haemolytic anaemias and in those non-regenerative anaemias in which reticulocyte percentage, but not reticulocyte production index (RPI), increased. The osmotic fragility could be used as an early indicator of erythrocyte regeneration.     

Genetic basis of cranial cruciate ligament rupture (CCLR) in dogs

Cranial Cruciate Ligament rupture (CCLR) is one of the most common forms of lameness in dogs and is analogous to rupture of the anterior cruciate ligament in humans, for which it can serve as a model. As there is a strong breed-related predisposition to CCLR in dogs, a study was undertaken to consider putative genetic components in susceptible dog breeds. A candidate gene, single nucleotide polymorphism (SNP) genotyping approach using MALDI-TOF mass spectrometry (Sequenom Ltd) was designed to investigate several CCLR-susceptible dog breeds and identify CCLR-associated genes/gene regions that may confer susceptibility or resistance. A meta-analysis was performed using the breed case/control candidate gene data to identify SNP associations that were common to the whole cohort of susceptible dogs. We identified SNPs in key genes involved in ligament strength, stability and extracellular matrix formation (COL5A1, COL5A2, COL1A1, COL3A1, COL11A1, COL24A1, FBN1, LOX, LTBP2) which were significantly associated with CCLR susceptibility across the dog breeds used in this study. These SNPs could have an involvement in CCLR due to a detrimental effect on ligament structure and strength. This is the first published candidate gene study that has revealed significant genetic associations with canine CCLR.     

Keeping dogs indoor aggravates infantile atopic dermatitis]

We had a two-month-old girl with severe dermatitis since birth. Her serum RAST to HD, Df and Dp were 1.06, 0.03 and 0.01 Ua/ml respectively. A Yorkshire terrier were kept at her mother's parents' home where the patient had lived for a month since birth. Her eczema, which became markedly aggravated whenever she visited there, improved after the elimination of the dog. We investigated the relationship between keeping dogs and infantile atopic dermatitis. We studied 368 patients under the age of two years (211 boys and 157 girls). Skin symptoms were graded globally mild, moderate or severe. Total serum IgE and specific antibody titer to dog dander were measured. We asked them whether they kept dogs and specifically, where they kept dogs, outdoor, indoor, in their own house, or in their grandparents' house. 197 patients had no contact with dogs, 90 patients kept dogs outdoor and 81 patients did indoor. The positive rate of RAST (> or = 0.7 Ua/ml) to dog dander was 6.1%, 17.8% and 46.9% respectively in these three groups. There were strong statistical differences between three groups. On the other hand, among the 81 patients who kept indoor, the RAST positive rates were almost same regarding where the dogs were kept, in their own house or their grandparents' house. Interestingly this difference happens only with patients under the age of 3 months. Patients older than 4 months showed no significant differences in the positive RAST rates, whether they kept dogs indoor or outdoor. This suggests the sensitization occurs before the age of 3 months. Speaking of symptoms, patients who kept dogs indoor showed significantly more severe symptoms than patients who had no contact with dogs and patients who kept dogs outdoor. There was no significant difference between the symptoms of patients who had no contact with dogs and those of patients who kept dogs outdoor. This implies the patient's symptom will improve only by moving the dog out of the house.     

Hemolytic anemia in Hodgkin's disease

In 12 of 128 patients with Hodgkin's disease (10%) haemolytic anaemia could be observed. In 3 of 12 patients an (auto-)immunological etiology of haemolysis was proven by the positive antiglobulin-test. In the rest of patients (9 of 12) the haemolytic syndrome could be explained by the concomitant enlargement of the spleen. In addition to high-dose prednisolone, splenectomy is the method of choice for the treatment of the haemolytic syndrome (4 of 6 patients). If adequate treatment of Hodgkin's disease is provided, the disease (2--37 months) will not be influenced by haemolytic anaemia.     

Seroprevalence of Toxoplasma gondii infection in shepherd dogs from Sarab District,Northwest Iran

The aim of this study was to compile initial epidemiological data on the prevalence of Toxoplasma gondii antibodies in Sarab area. We evaluated the titers of anti-T. gondii antibodies by latex agglutination test (LAT; titer?>?1:64) serological test in 39 (10.1 %) serum samples from shepherd dogs exhibiting clinical signs of infectious diseases. The largest age group was 2–4 years, with 170 (44.3 %) dogs out of which only 21 dogs (12.3 %) were seropositive and the lowest age group was 4–6 years, with 87(22.6 %) out of which only 3 dogs (3.4 %) were seropositive. The highest rate of infection was seen in Ardaha village, with 11 (27.5 %) dogs. The lowest rate of infection was detected in Khaki and Asbfroshan villages, with only one dog. According to dog breed, the seropositivity rate of T. gondii was 14.3 % in pure breed dogs and 11.2 % in mongrel dogs. No sex or breed predispositions to T. gondii infection were detected during this serological assays (P?≤?0.05). The antibody titres of T. gondii ranged from 1:64 to 1:2,084. 39 Seropositive dogs with titers of 1:64 in 10, 1:128 in 13, 1:256 in 5, 1:512 in 6, 1:1,024 in 3, and 1:2,084 in 2 dog. In the present study, there was no correlation between antibody titers and, age or location. Our results show that presence and exposure of shepherd dogs to T. gondii in Sarab city confirm that dogs are exposed to T. gondii and play an important role in the epidemiology of T. gondii of this region.     

Epidemiological, clinical and parasitological data about canine leishmaniasis in Tunisia

Epidemiological, clinical and parasitological data concerning canine leishmaniasis were collected in two Tunisian populations of dogs, different in breed and life style: 23 rural dogs and 26 dogs of European breeds. All were symptomatic and lived in the north of Tunisia where human visceral and cutaneous leishmaniasis caused by Leishmania infantum are endemic. Leishmaniasis has been confirmed in all dogs by serology or/and by parasitic identification. Significant differences concerning age and symptoms suggest a higher susceptibility to infection in European imported breeds. In fact individuals of this population were significantly younger; 81% were less than 5 years old whereas 57% of the autochthonous rural dogs were more than 5 years old with 31% of them being older than 9 (p = 0.014). In spite of their young age, 75% of imported breeds presented an affection of their general state with more frequent cutaneous symptoms than the rural dogs (96% versus 69%, p = 0.02). Isoenzyme typing of 31 strains, obtained from the two populations, from different sites (blood, lymph nodes, spleen) has only identified the zymodeme Leishmania infantum MON-1. This stresses the need of more investigations to determine reservoirs of the other enzymatic variants identified in humans in Tunisia and Mediterranean basin.     

Canine DLA diversity: 2. Family studies

The canine Major Histocompatibility Complex is referred to as DLA (for dog leukocyte antigen). There are no published studies on DLA segregation in the dog, so this part of the DLA workshop aimed to collect DNA from multigeneration families of different breeds of dogs. Twenty-two families of dogs were submitted to the workshop, comprising 313 individuals, of which 247 had one or both parents available.     

Hair Whorls in the Dog (Canis familiaris). I. Distribution

Hair whorl characteristics were assessed in the domestic dog (Canis familiaris) in the regions of cephalic, cervical (dorsal, ventral, and lateral), thoracic and brachial axillary regions, the chest, shoulders, elbows, ventral abdominal region, and on the caudal thighs (ischiatic). They were classified as simple or tufted, and their position was recorded as the distance between their centers and bony landmarks within each region. The distribution of whorls was explored in a cohort of domestic dogs (N = 120) comprising a variety of breeds and cross‐breeds, sourced from shelters (N = 60) and the general public (N = 60). Whorls observed in the majority of dogs in this cohort typically occurred on the chest, brachial axillary region, elbows, and ischiatic region. Atypical whorls were present in fewer than 20% of the population, and included those on the head (cephalic), cervical regions (dorsal, ventral, and lateral), shoulders, thoracic axillary region, and on the ventral abdominal region. The majority of whorls on dogs were classified as simple. In contrast, those located on the elbows and the majority of chest whorls were tufted. The presence and position of whorls were often associated with several variables including coat length and thickness, and the sex and source of the dog. The palpation and hair‐cluster method of whorl assessment described in this article is best suited to dogs with short‐to‐medium coat lengths. The current methodology developed to assess hair whorl characteristics provides a framework for future investigations into any associations between hair whorl characteristics and other canine traits such as temperament. Anat Rec, 293:338–350, 2010. © 2010 Wiley‐Liss, Inc.     

Decreased lipid fluidity of the erythrocyte membrane in dogs with leishmaniasis-associated anaemia

In both man and the dog, anaemia resulting from natural leishmaniasis is often severe and mainly associated with a shortened life span of erythrocytes. Lipid fluidity of erythrocyte membranes from 17 dogs with anaemia caused by visceral leishmaniasis was investigated by means of fluorescence polarization. Results were compared with those from three groups of control animals (10 healthy dogs, seven dogs with visceral leishmaniasis but no anaemia, and 10 dogs with anaemia unrelated to leishmaniasis). Fluorescence polarization values recorded for animals with leishmaniasis-associated anaemia were elevated-indicating reduced erythrocyte membrane fluidity-and significantly higher than in the control groups. Mechanical sequestration by the spleen due to increased cell rigidity, or alterations in receptor/ligand erythrocyte cytoadherence mechanisms, or both, may result from decreased membrane fluidity and hence contribute to the anaemia of Leishmania -infected dogs.     

Canine echinococcosis in northern Jordan: increased prevalence and dominance of sheep/dog strain

A total of 112 stray and semi-stray dogs (Canis familiaris) from four different geographical areas in northern and middle Jordan were necropsied to evaluate the prevalence and intensity of intestinal helminthiasis. Of these, 33 dogs (29.5%) were infected with Echinococcus granulosus and 61 (54.5%) with other Taenia species. Other cestodes found included Dipylidium caninum in 36 dogs (32.1%), Diplopylidium in 6 dogs (5.4%), Mesocestoides sp. in 3 dogs (2.7%) and Joyuexiella in 1 dog (0.9%). Toxocara nematodes were found in 10 dogs (9.2%) and only 1 dog was positive for acanthocephalans. Among the dogs infected with E. granulosus, 8 dogs (24.2%) had a worm load higher than 1,000 worms. The ratio of infected male to female dogs was 1.9:1.0. Strain analysis of E. granulosus using random primers revealed the dominance of the G1 strain (sheep/dog strain) in the region. Only one dog harbored another E. granulosus strain, which resembled the G4 strain pattern.